CCPO
Circulation
a publication of the Center for Coastal Physical Oceanography
Vol. 12 No. 1
Spring 2005
Large Eddy Simulation of Langmuir
Circulation in Shallow Water
by Dr. Chester Grosch
Professor of Oceanography
Professor of Computer Science
In this issue:
Large Eddy
Simulation of Langmuir
Circulation in Shallow
Water
The Chesapeake Interactive
Modeling Project
Notes from the Director
CCPO Profiles
Blue Crab Bowl 2005
Class Trip on the
R/V Fay Slover
Meeting & Workshop
Report
Just the Facts
Langmuir circulation consists of
pairs of parallel counter-rotating vortices
(or cells) oriented approximately in the
wind direction and often occurs in the
wind- and wave-driven surface mixed
layer of lakes and oceans. The presence
of Langmuir cells is most readily marked
by the presence of lines of foam and/or
algae on the water surface. Although there
were earlier reports of “streaks” on the
ocean surface, Langmuir cells were first
described by Langmuir in 1938. His
observations can be summarized by: 1)
the wind generates vortices and not
convective instability; 2) the downwelling
motion under the surface convergences is
more intense than the upwelling; and 3)
the downwind motion of the water at the
surface convergences is faster than
outside the convergence zone.
Since Langmuir’s description,
there have been many additional
observations, comprehensively summarized in S. Leibovich’s 1983 review
article and, very recently, by A.S.
Thorpe in 2004. Improvements in
instrumentation, including vertical
profilers and backscatter, sidescan and
Langmuir supercells provide a possible
explanation for these dark lines in a
turquoise sea, observed on a shallow
Bahamian shelf by Old Dominion
University’s Dick Zimmerman and David
Burdige. Divers found that the dark
bands, aligned roughly with the wind,
were made up of slightly negatively
buoyant algae, possibly swept into bottom
convergences associated with Langmuir
cells just as surface foam is swept into
their surface convergences. The observed
line spacing of roughly three times the
water depth is consistent with LEO-15
observations and modeling of Langmuir
cells that fill the entire water column.
Photograph by Laura Bodensteiner, Moss
Landing Marine Laboratories.
(continued on page 2)
The Center for Coastal Physical Oceanography “. . . facilitating innovative research in the coastal ocean.”
established 1991
Doppler sonar observations of bubble clouds, have led to, in
Thorpe’s words, “a radical change in understanding the
phenomena.” In addition, since about 1995, there have been a
few large-eddy simulations (LES) of Langmuir circulation in
the surface mixed layer of the deep ocean, and the results of
these have also helped increase our understanding of the
complexity of the phenomena. Langmuir circulation is now
believed to be a turbulent process driven by the interaction of
waves and currents.
Very recently, Ann Gargett, professor of
oceanography, and Judith Wells, postdoctoral research
scientist, using a five beam VADCP in shallow (approximately
15 M) water at LEO-15 off the southern coast of New Jersey,
observed Langmuir circulation cells. As far as we know, these
are the first observations made in shallow water. As Gargett et
al. noted in their 2004 Science article, the observations showed
Langmuir circulation cells extending throughout the entire
water column during strong wind and wave forcing. These
As compared with a LES without the Langmuir force, the profile
is very uniform throughout most of the water column with thin
surface and bottom boundary layers. The effect of the Langmuir
circulation is to homogenize the water column in the mean.
Contours of the vertical and cross-stream distribution of
the mean turbulent velocity fluctuations are shown in the second
figure. In this figure, the panels show, from top to bottom, the
streamwise, the vertical and the cross-stream velocity components.
These have been averaged in time as well as over the streamwise
length of the computational domain and the corresponding mean
velocity components have been subtracted. The vertical axis is
height from the bottom and the horizontal axis is the cross-stream
distance. Overall, the flow has a single cell structure in contrast
with a flow without the Langmuir force (not shown) which had a
double cell structure. (Doubling the width of the computational
box resulted in two cells.) In addition, the extrema of these
fluctuating components are from two to ten times greater than
those of a flow without the Langmuir force (again, not shown).
Figure 2. Contours of the
vertical and cross-stream
distribution of the mean
turbulent velocity fluctuations. The panels show,
from top to bottom, the
streamwise, the vertical
and the cross-stream
velocity components. The
depth (0 to -H) has been
scaled by the half depth
and mapped into -1 to 1.
The width is also scaled
by the half depth.
Figure 1. Mean profile of
the streamwise velocity
component as a function of
depth for LES of wind
stress driven flow with and
without the Langmuir
forcing. The depth (0 to
-H) has been scaled by the
half depth and mapped into
-1 to 1 to facilitate the
computation.
observations showed downward advected clouds of air
microbubbles originating at the surface and upward advected
bottom sediments. In parallel with the observations, Andres
Tejada-Martinez, postdoctoral research scientist, and I have been
carrying out LES of Langmuir circulation in shallow water.
LES is based on resolving the large, energy containing
eddies and modeling the rest of the spectrum. LES is a wellknown numerical approach. However, the key to successful
application of LES methodology to simulating Langmuir
circulation is the correct incorporation of the forcing mechanism
which drives the circulation. A theoretical model of Langmuir
circulation was first proposed by A. D. D. Craik and S. Leibovich
in 1976. This model has a Langmuir force, given by the cross
product of the Stokes drift velocity of the waves and the current
vorticity, added to the Navier-Stokes equations. In both theoretical
and prior LES calculations for deep water, it was shown that the
Langmuir force resulted in the quantitative and qualitative
reproduction of all of the observed features of Langmuir
circulation.
Our LES was driven by a wind stress at the surface in
addition to the Langmuir force whose Stokes drift incorporated
wave frequency and amplitude; both the stress and the values of
the wave parameters were chosen to be consistent with the
observations of Gargett and Wells. A stretched grid was used to
resolve the free surface and bottom boundary layers. The mean
velocity profile resulting from our LES is shown in the first figure.
As seen in the figure, the flow has an intensification of
the positive streamwise fluctuating component near the surface
and near the bottom, in close agreement with the observations of
Gargett and Wells in 2005 and Gargett et al. in 2004. A region of
positive streamwise velocity coincides with a region of negative
vertical velocity and vice-versa. Regions of positive vertical
velocity are upwelling limbs and negative vertical velocity are
downwelling limbs. At mid-depth, the ratio of spanwise length of
the upwelling limb to spanwise length of the downwelling limb is
1.6, in close agreement with the observed value of 1.5. Finally,
the magnitude of the velocity in the downwelling limbs is greater
than in the upwelling limbs in both the observations and in the
simulation.
LES of Langmuir circulation in a shallow water winddriven current showed major changes in the turbulence
dynamics as compared to the case without Langmuir forcing.
The presence of Langmuir forcing results in intense turbulent,
streamwise vortical structures with strong streamwise jets near
the surface and bottom. The net effect is a major enhancement
in vertical mixing. As pointed out by Thorpe, the effects of
Langmuir circulation are important enough to be included in
ocean mixed layer and general circulation models. This has
not yet been done, presumably because of the difficulty in
parameterizing them. This is a difficult problem but we have
begun a study of it.
2
Dr. Grosch wins the University Faculty Research Award
by Dr. John Klinck
Scientists gather information, determine relationships, and create tools for observing and understanding nature. Most
scientists consider questions that pique their interests; creative scientists often have a wide range of interests.
Dr. Chester E. Grosch, who has been part of CCPO from the beginning, displays such a range of interests. He has won
this year’s annual Faculty Research Award from Old Dominion University for a research career spanning three decades. His
early interests involved the fluid dynamics of surface waves, which expanded to boundary layers and dynamical instability. He
was active in the early days of computational fluid dynamics which led to a study of numerical methods, programming techniques
and calculating on multiple, linked computers. His interests further expanded to turbulence, compressible flow and combustion.
Recent papers analyze trends in long term observations and their relationship to climate change. His most recent research is
large-eddy simulation (LES) of Langmuir circulation in shallow water.
However varied, and incomplete, this list of interests may be, a compelling characteristic of Chet’s work is his willingness
to work with colleagues and students, as evidenced by the author list on his publications. Chet displays the character of a true
academic. He has read widely and has studied some exotic problems. He is an interesting participant in almost any conversation;
I learn something every time he speaks, whether the topic is physics, opera or sports.
CCPO is privileged to have Chet as a member. We congratulate him on his award and look forward to many stimulating
discussions.
The Chesapeake Interactive
Modeling Project: Bringing
Numerical Models to the Public
the interface is designed, it should be relatively straightforward to
apply the framework to other marine systems, such as the San
Francisco Bay, Puget Sound, or Lake Superior.
We have two target audiences in mind for the initial stage of
this project. The first is museum-goers. We envision kiosks in science
museums and aquaria running the model, with accompanying text to
enhance the experience by giving the user some insight into the
processes being demonstrated. The second audience is the classroom,
at a wide variety of levels. Such a model could be used in K-12
classrooms, and by invoking user-selected levels of sophistication in
by Dr. Jay Austin
Numerical models of ocean circulation have long used
primarily by oceanographers, and at that, only useful to those who
are willing to make a serious commitment of time in order to learn
how to use them effectively. They require a certain degree of
programming expertise, and, until the last few years, all but the smallest
models have required specialized computing facilities. Most of all,
they require patience; typically, numerical models are run in an
asynchronous mode, where a user sets up initial conditions, describes
forcing conditions, compiles and runs the model, and then displays
stored model fields. This process takes days, weeks or even months,
depending on the complexity of the model. These limitations have
put numerical modeling off limits to all but the most committed.
The Chesapeake Interactive Modeling Project, currently
funded by the Office of Research at Old Dominion University, is
attempting to remove these barriers. We have formed a collaborative
team of investigators (Mike Dinniman, Liz Smith, and myself at
CCPO, and Jessica Crouch, Lee Belfore, and Yuzhong Shen at the
Virginia Modeling, Analysis and Simulation Center) to develop a
relatively simple but informative model of the Chesapeake Bay, which
can be run on a commercially available PC platform, and will use a
graphical user interface which will allow the user to adjust parameters
such as freshwater runoff and wind forcing and observe the response
in real-time. The challenge of this project, beyond the considerable
coding that is going into the graphical front end, is striking a balance
between model fidelity and speed, so that the model reproduces the
physics of estuarine circulation faithfully, but does so quickly enough
to retain the interest of a casual user. While this initial phase is focusing
strictly on hydrodynamic forcing, I anticipate that subsequent funding
will allow us to incorporate simple biological models. These would
allow a casual user to, for example, drag chicken farm icons over to
the Eastern Shore and observe the impact on oyster populations, or
change land use distribution in Pennsylvania and see how the added
nutrients or sediment impacts the ecosystem of the bay. Also, once
A conceptual
screenshot of a
g r a p h i c a l
interactive user
interface for a
numerical
model of the
Chesapeake
Bay
the types of forcing and outputs, could be useful in undergraduate
and even graduate education. In a subsequent stage, I am interested
in adapting these techniques to the needs of researchers, who could
use interactive models to develop intuition about a particular system
by interacting with it in real time before applying more stringent
modeling techniques. With advances in computing technologies and
the maturation of numerical models, these sorts of techniques should
allow us, over time, to allow a far wider audience of casual users
access to numerical models as a teaching tool, and also allow
researchers to be less distracted by the mundane details of numerical
modeling and allow us to focus more fully on science.
3
Notes from the Director
The Center for Coastal Physical Oceanography is an abstract entity to
many, but it is really a group of people with various backgrounds, levels of
experience, personalities and motivations. The Center is also a creative engine
that fosters expansion of our understanding of the processes at work in our world.
The Center depends on creative, motivated people to be successful.
Our contributions are often limited to the arcane world of technical
literature. It is important that others in the University and the general public hear
about the high quality of the people at the Center. The recent University Annual
Faculty Research Award presented to Chet Grosch is an important recognition of
his contribution. Many faculty and research scientists are invited to science panels
providing steering, oversight and evaluation which is implicit recognition of their
value. Graduate students contribute to the Center by the research that they do, the
papers they write and the meetings that they attend. Most of the Ph.D. students
continue their careers after graduation in postdoctoral or faculty positions, a
testament to their quality.
Awards recognize individuals and provide them a moment in the spotlight.
This recognition of individuals reflects well on all of us and the work that we are
doing. Keep up the good work.
John M. Klinck
CCPO People Profiles
for scheduling, budget, and finance for Fay Slover and the small
boats of OEAS, with an occasional stint as relief captain.
Dick is probably proudest of helping to successfully
steer a resolution last year by the University to establish a
channel and pier at the Sailing Center location on the Elizabeth
River in order to accommodate Fay Slover and other small-tomedium class research vessels. Although years away, it will
be part of a larger Tidewater marine complex planned by the
University which will focus on marine interests of the region.
Dick Moody has been a
staff member at CCPO for five
years. After retiring from the
NOAA Corps with the rank of
Commander in 1988, Dick tried
his hand at the corporate world,
working in sales for Kraft Foods
for eight years. Missing the
intellectual stimulation of the
sciences, Dick found his old
friend Larry Atkinson as the oceanography department chair
at Old Dominion University and decided to upgrade his 30year old B.S. in biological oceanography by becoming a student
once again. After an interesting couple of years attaining an
M.S., Dick became the Old Dominion University liaison to the
NOAA-at-Nauticus office in downtown Norfolk. When
Arnoldo Valle-Levinson needed help with his Chesapeake Bay
and estuarine field work, Dick jumped at the chance to get back
into “operational oceanography.” Two years later after various
ADCP operations and instrument deployments/recoveries
aboard university, private research, and government vessels
from North Carolina to Maryland (and one cruise in the East
China Sea), his attention turned to the new vessel being built
to replace the R/V Linwood Holton. Dick obtained a Captain’s
license from the Coast Guard and became the interim captain
of the new vessel, R/V Fay Slover, overseeing itsconstruction
in Somerset, MA. He then brought the vessel to Norfolk,
operating it for the first seven months. Captain Richard Cox
was then brought on board to operate the R/V Fay Slover, and
Dick stayed on as Marine Superintendent, with responsibilities
Michael Ott came to
CCPO as a post-doc in July of
2004. He grew up in a small town
in central Labrador. As an
undergraduate, he studied physics
and math at the University of
Waterloo and participated in the
cooperative program where he
researched holographs at Ontario
Hydro. He also studied
magnetohydro-dynamics at Technische Universiteit Eindhoven
in the Netherlands. Michael earned his Ph.D. in physical
oceanography at the University of Victoria, focusing on the
dynamics of fjord-type estuaries. After three years at Oregon
State University studying coastal wind-driven transport and
mixing, he is happy to return to estuarine research,
incorporating observations, dynamical studies, and numerical
modeling. His wife, Laura, has an M.A. in history, and when
their 2 year-old son, Jared, is not keeping him busy, Michael
enjoys camping, watching hockey, and swimming, especially
in the ocean. Norfolk is the first place he has lived where the
ocean is not too cold for long swims.
4
CCPO are co-directors of the bowl. More than 60 faculty, staff
and graduate students from both institutions donated many hours
of their time to ensure the success of this exciting event. CCPO
personnel who volunteered during the event were: Ann Gargett,
Sinan Husrevoglu, Michael Ott, Mayra Riveron-Estianzaga,
Joe Ruettgers, David Salas, Robert Tuleya, Arnoldo ValleLevinson, and Judith Wells.
Chesapeake Bay Governor’s School,
Warsaw Campus Wins Blue Crab Bowl
in Dramatic Overtime Finish
In a cliffhanger race that ran into overtime, the
Chesapeake Bay Governor’s School, Warsaw Campus, emerged
as champion in the Blue Crab Bowl, held Saturday, February
12 at the Virginia Institute of Marine Science campus at
Gloucester Point, VA.
The Blue Crab Bowl is a Virginia regional academic
tournament focusing on ocean science. Eighty students from
16 high schools statewide spent the day in heated competition.
The winning team from Tappahannock landed an all-expensespaid trip to the 8th Annual National Ocean Sciences Bowl
(NOSB®) in Biloxi, MS to compete against 24 other regional
champions where an expected 2,000 students will represent
375 high schools from around the country.
Eighth Grade Class Trip on the R/V
Fay Slover
The eighth grade science class from Christ The King
(CTK) School in Norfolk, VA, took a short cruise on Old
Dominion University’s research vessel, the R/V Fay Slover,
on April 19. The cruise came about because Ms. Jan Mislan,
the eighth grade science teacher at CTK, stresses hands-on
experiences as a way to provide students with a better
understanding of the concepts and ideas that are taught in the
classroom. Twenty-one CTK students were met on board the
R/V Slover by Mates Laura Gibson and Patrick Curry and
Captain Richard Cox. CCPO scientists, Olga Polyakov and
Eileen Hofmann, and program specialist, Julie Morgan, went
along to answer questions and to provide assistance. Additional
Blue Crab Bowl
2005 Champions
from
the
The
Chesapeake Bay
Governor’s School
for Marine and
Environmental
Science in Warsaw.
Pictured at far left is
the team Coach,
Kevin Goff.
Two eighth grade
students from Christ
The King School
prepare to deploy a
plankton net from
the stern of the R/V
Fay Slover
Organized as a round-robin, double elimination
contest, the Blue Crab Bowl uses questions designed by marine
scientists to test the students’ knowledge of oceanography,
geology, biology, and maritime history. Participation in the
bowl with the guidance of their teacher coaches not only
broadens the students’ awareness and understanding of the
oceans, but also provides a forum for students who excel in
math and science to receive regional and national recognition
for their diligence and talent.
Chesapeake Bay Governor’s School, Warsaw played
back-to-back competitions, both requiring overtime tiebreaking questions in order to take the laurels. Hot on their
heels in second place was Bishop Sullivan Catholic High School
of Virginia Beach. Third place went to Maury High School of
Norfolk, and Fauquier High School in Warrenton held fourth
place. The awards were presented by Dr. Cynthia Suchman,
Assistant Director of Virginia Sea Grant, the agency funding
the uniquely-crafted ceramic “crab bowls.”
The Blue Crab Bowl is a cooperative effort between
the Department of Ocean, Earth, and Atmospheric Sciences,
the Center for Coastal Physical Oceanography, Old Dominion
University, and the Virginia Sea Grant Marine Advisory
Program at the Virginia Institute of Marine Science, College
of William and Mary. Liz Smith and Anne West-Valle of
support was provided by Carolyn McKenna and Father Brian
Rafferty from CTK School.
After a safety briefing, the R/V Slover got underway for
a short trip down the Elizabeth River. During the first part of the
cruise, the CTK students learned about oceanographic equipment
and ship operations. On the return portion, the students did a CTD
cast, a plankton net tow, a bottom mud grab, and collected water
by hanging Niskin bottles on a wire. The students deployed and
retrieved the equipment with the assistance and oversight of Laura
Gibson and Patrick Curry. Checking out the net sample with a
microscope was fun for everyone because a plankton bloom in
the Elizabeth River provided many different organisms for viewing.
The bottom mud sample, which contained many worm tubes, was
thoroughly examined.
The cruise on the R/V Slover was the start of a marine
sciences-oriented science module for the eighth grade students at
CTK School. This is part of a larger effort by Ms. Mislan and
other faculty to introduce marine science concepts into the overall
curriculum at CTK School.
5
Meeting & Workshop Reports
to all of the groups, such as wireless communications. These
presentations were followed by a discussion of data management
and the upcoming CBOS-CEID (Cooperative Expansion and
Integration Demonstration) deployments of real-time wave
measurement systems in the Bay by Old Dominion University,
HPL, and VIMS. Many people have expressed a strong desire to
hold these technical service meetings on a regular basis, hopefully
with a more specific focus than that of this introductory meeting.
The continued open exchange of technical experience will more
quickly lead to a better Chesapeake Bay Observing System.
Southern Ocean GLOBEC Workshop
A workshop was held at CCPO, January 6-8, 2005, which
had the objective of facilitating the development of synthesis and
integrative studies of the extensive multidisciplinary data sets that
were collected as part of the U.S. Southern Ocean Global Ocean
Ecosystems Dynamics (SO GLOBEC) field programs. The
workshop, which was attended by about 25 science investigators,
started with presentations that provided updates on analyses and
modeling efforts that have been ongoing since the end of the field
program. Some of these results are reported in volume 51 of DeepSea Research II, which was published in December 2004.
Following the presentations were discussions about continued
analyses and modeling of the SO GLOBEC data sets. These
discussions led to identification of overarching research themes
related to understanding the physical environment, overwintering
strategies of Antarctic krill, habitat use and predator-prey
interactions, and processes that allow biological hot spots to form
and persist. Research programs designed to address these themes
are now being developed. These synthesis and integration studies
of the SO GLOBEC data set are part of a larger effort being
undertaken by the U.S. and International GLOBEC programs.
QARTOD II: Waves & Currents
From February 28-March 2, the second workshop on the
Quality Assurance of Real-Time Ocean Data (QARTOD) II: Waves
and Currents for the coastal ocean observing community was
hosted by Larry Atkinson of the Center for Coastal Physical
Oceanography and Mark Bushnell of NOAA OSTEP at Nauticus,
the National Maritme Center and the Sheraton Hotel. Over 70
participants from federal and state governments, academia, and
industry attended the workshop. The meeting addressed in situ
currents, remote currents (high frequency radar), and waves.
ChesTech: Chesapeake Bay Technical
Service Providers Meeting
QARTOD II
participants at
the Sheraton in
Norfolk, VA
As more and more emphasis is placed nationally on realtime observing, the technical problems that face observers in the
Chesapeake Bay become more daunting. The increased technical
demands are placed not only on the Principal Investigators at
various institutions around the Bay, but disproportionately on
technical staff who are actually designing, constructing and
deploying the real-time observing systems. However, the “techs”
rarely, if ever, meet each other at regional meetings, which tend to
be attended largely by scientific faculty. After a particularly
enjoyable visit to the Virginia Institute of Marine Sciences, during
which Jay Austin, research assistant professor, spent quite a bit
of time talking with their technical staff (and wishing that the Old
Dominion University techs were along to ask the right questions),
he decided to do something about it.
On January 10, CCPO hosted the first ChesTech meeting.
There were roughly 35 participants, with people from as far away
as Horn Point Labs and UNC Wilmington. There were five
presentations, one from each of the five labs (Chris Powell for
Old Dominion University, Todd Nelson for VIMS, Randy Cone
for HPL, Mark Bushnell for NOAA OSTEP, and Chris Heyer for
Maryland DNR), discussing the nuts and bolts of their experience
with real-time systems. These presentations were met with lively
discussion, and allowed participants to identify challenges common
All working groups were asked to answer the following
specific questions relevant to their topic:
· What real-time quality control tests should be
applied?
· What categories of real-time quality descriptor flags
should be applied?
· What real-time metadata descriptors should be applied?
· What real-time calibration flags should be applied?
· What common data formats should be applied?
· Additional requirements associated with the Data
Management and Communications (DMAC) Plan?
· Next steps and roadblocks to implementation of QA/
QC?
There were discussions regarding the role of this group in the
overall Ocean.US DMAC process. The group felt that it would be
worthwhile to become the real-time data group within the DMAC
organization.
6
Just the Facts
Publications
Friedrichs, M.A., R. Hood, and the Regional Ecosystem Modeling
Testbed Team, “The regional ecosystem modeling intercomparison
project,” oral presentation, European Geosciences Union Meeting,
Vienna, Austria, April 25-29, 2005.
Kim, H.-C. and E.E. Hofmann, “Evaluation and Derivation of
Cloud-Cover Algorithms for Calculation of Surface Irradiance in
Sub-Antarctic and Antarctic Environments,” Antarctic Science, 17,
135-150, 2005.
Gargett, A.E., “Ocean turbulence: observation and interpretation,”
seminar presentation, Aerospace Engineering Department, Old
Dominion University, Norfolk, VA, February 25, 2005.
Knutson, T., R.E. Tuleya, W. Shen, and I. Ginis, “Impact of
climate change on hurricane intensities,” in Hurricanes and
Typhoons: Past, Present, and Future, R. Murname and K. Liu, eds.
Columbia University Press, pp. 408-439, 2004.
Hofmann, E., Friedrichs, M. and the U.S.ECoS Science Team,
“U.S. Eastern Continental Shelf Carbon Budget: Modeling, Data
Assimilation, and Analysis,” poster presentation, Ocean Color
Research Team Meeting, Portland, OR, April 12-14, 2005.
Tejada-Martinez, A.E. and K.E. Jansen, “On the interaction
between dynamic model dissipation and numerical dissipation due
to streamline upwind/Petrov-Galerkin stabilization,” Computer
Methods in Applied Mechanics and Engineering, 194, 1225-1248,
2005.
Hofmann, E.E., J.M. Klinck, and E.N. Powell, “Estimating hard
clam (Mercenaria mercenaria) age-length from a theoretical
model,” oral presentation, National Shellfisheries Association
Meeting, Philadelphia, PA, April 10-14, 2005.
Presentations
Hofmann, E.E., “Modeling Larval Transport,” seminar
presentation, University of Maryland Center for Environmental
Science, Horn Point Laboratory, Cambridge, MD, December 8,
2004.
Carr, M.-E., M.A. Friedrichs, and M. Schmeltz, and the PPARR3
group, “A comparison of global estimates of marine primary
production from ocean color,” oral presentation, Ocean Color
Research Team Meeting, Portland, OR, April 12-14, 2005.
Hofmann, E.E., “Modeling marine plankton distribution and
transport,” Marine Environmental Biology Section Seminar,
University of Southern California, Los Angeles, CA, January 18,
2005.
Christian, J.R., and M.A.M. Friedrichs, “Recent developments in
data assimilation in ocean biogeochemistry,” oral presentation,
Canadian Meteorological and Oceanographic Society 39th Annual
Congress: Sea to Sky, Vancouver, British Columbia, Canada, May
2005.
Hofmann, E.E., “Antarctic Research,” oral presentation, Altrusa
International, Tidewater Chapter, Norfolk, VA, March 21, 2005.
Hofmann, E.E., “Shellfish Diseases and Ecological Health,” guest
lecture, Human Health and Global Environmental Change Course,
Harvard Medical School/Harvard School of Public Health, Boston,
MA, March 8, 2005.
Dinniman, M.S., J.M. Klinck, W.O. Smith, Jr. and E.E.
Hofmann, “The Influence of Sea Ice Cover on Circulation and
Nutrient Processes in a Numerical Circulation Model of the Ross
Sea, Antarctica,” poster presentation, 2005 Gordon Research
Conference on Polar Marine Science, Ventura, CA, March 13-18,
2005.
Paillard, C., F. Jean, J. Flye Sainte-Marie, S.E. Ford, E.N. Powell,
J.M. Klinck, and E.E. Hofmann, “An integrated approach to
bacteria-bivalve interactions: development of a vibriosis model in
Manila clams,” oral presentation, National Shellfisheries
Association Meeting, Philadelphia, PA, April 10-14, 2005.
Flye Sainte-Marie, J., F. Jean, C. Paillard, J.M. Klinck, E.E.
Hofmann, S.E. Ford, E.N. Powell, “Modeling brown ring disease
in the Manila clam (Ruditapes philippinarum): the individual host
model,” oral presentation, National Shellfisheries Association
Meeting, Philadelphia, PA, April 10-14, 2005.
Powell, E.N., K. Alcox, J. Kraeuter, J.M. Klinck, and S.E. Ford,
“The Delaware Bay oyster beds of New Jersey; Compensatory
recruitment, depensatory mortality, and reference point-based
management,” oral presentation, National Shellfisheries
Association Meeting, Philadelphia, PA, April 10-14, 2005.
Ford, S.E., E.N. Powell, J. Flye Sainte-Marie, F. Jean, C. Paillard,
J.M. Klinck, and E.E. Hofmann, “Brown ring disease: the
integrated model,” oral presentation, National Shellfisheries
Association Meeting, Philadelphia, PA, April 10-14, 2005.
Royer, T.C., “Alaskan Oceanography: Past, Present and Future – A
Personal Perspective,” keynote speaker, Alaska Marine Science
Symposium, Anchorage, AL, January 25, 2005.
Friedrichs, M.A., R.R. Hood, J.D. Wiggert, and E.A. Laws,
“Assessing the costs and benefits of increasing ecosystem model
complexity using data assimilation,” oral presentation, 2005
Aquatic Sciences Meeting, ASLO, Salt Lake City, UT, February
20-25, 2005.
Tejada-Martinez, A.E., “Approximations and models of the
subgrid-scales in large-eddy simulation,” invited seminar, Institute
(continued on page 8)
7
Presentations cont’d.
Ph.D. Students
for Computational Engineering and Sciences, University of Texas,
Austin, TX, March 31, 2005.
Salihoglu, B., “Modeling the Effects of Physical and Biogeochemical
Processes on Phytoplankton Species and Carbon Production in the
Equatorial Pacific Ocean,” December 2004, Advisor: E.E. Hofmann.
Taken a position at LEGOS/CNRS in Toulouse, France.
Tuleya, R.E., “Using Computer Models to Forecast Present Day and
Future Hurricanes,” oral presentation, ExxonMobil Research and
Engineering, Warren, NJ, February 17, 2005.
Tuleya, R.E., “Hurricane Model Transitions to Operations at NCEP/
EMC,” oral presentation, NCEP/EMC National Center for
Environmental Prediction/Environmental Modeling Center, Camp
Springs, MD, March 8, 2005.
Valle-Levinson, A., “The role of friction and Earth’s rotation on
water exchange in semi-enclosed basins,” oral presentation,
University of Florida, Gainesville, FL, February 28, 2005.
Wiggert, J.D., A.G.E. Haskell, G.-A. Paffenhöfer, E.E. Hofmann,
and J.M. Klinck, “Sustaining Copepod Populations Under
Oligotrophy: The Role of Feeding Behavior,” oral presentation, 2005
Aquatic Sciences Meeting, ASLO, Salt Lake City, UT, February 2025, 2005.
Committees
6CN05
The Center for Coastal Physical Oceanography
Old Dominion University
Crittenton Hall
786 W. 52nd Street
Norfolk, VA 23529
USA
Hofmann, E.E.
Attended U.S. GLOBEC Science Steering Committee meeting, St.
Petersburg, FL, May 4-6, 2005.
CCPO Circulation is published three
times a year. Please contact the editor
for more information at 757-683-5548
or www.ccpo.odu.edu.
Hofmann, E.E.
Attended North American Carbon Program Science Steering Group
meeting, Washington, DC, April 28-29, 2005.
The researchers and staff of the Center for Coastal Physical
Oceanography are involved in many outreach projects in our
region, Hampton Roads. Recently, students from a local school,
Christ The King in Norfolk, VA, participated in a field trip
on the R/V Fay Slover. In the above image, two eighth grade
students assist R/V Fay Slover Mate Patrick Curry in lowering a Niskin bottle to collect a water sample for observation.
Editor.................Gabriel Franke
Technical Editor....Julie Morgan
Hofmann, E.E.
Attended the University-National Oceanographic Laboratory System
(UNOLS) Council meeting, Washington, DC, March 29-30, 2005.